Jeep TJ 4.0 turbo tuning and build (basemap for GM 2 bar map sensor)

Show me someone who's one a boosted forged stroker that's reliable and didn't cost over $10k. I'm not doing the swap to show it off I'm doing the swap because I have a heavy foot and want to beat the balls off my jeep and want a reliable 300+hp

well then :)
 
Show me someone who's one a boosted forged stroker that's reliable and didn't cost over $10k. I'm not doing the swap to show it off I'm doing the swap because I have a heavy foot and want to beat the balls off my jeep and want a reliable 300+hp

There're good reasons ls swaps are so popular.

For a boosted 4.0 I don't see stroking as good value. Get forged pistons for sure. I doubt that stock rods are too risky at 300, and I'd be surprised if the crank needed upgrading.
 
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Price varies drastically depending on how much you are able to DIY. If you have to pay a shop it might be difficult to stay under 10K.
 
If you want reliable, dont do an LS swap. Or any V8 swap. Its alot easier to work on the inline 6 than a v8. I finally saw one of these " cheap LS swap" TJs. My friends brother bought one. its terrible. yea its fast and it sounds great but we will probably spend the next 2 years redoing wiring. Stuff barely fits.

Meanwhile my crap box makes about 5psi boost with the supercharger. Stock motor, headers, etc. it still damn near lifts a wheel off the ground. People hate riding in it because its fast and clearly, unsafe. LOL
 
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If you want reliable, dont do an LS swap. Or any V8 swap. Its alot easier to work on the inline 6 than a v8. I finally saw one of these " cheap LS swap" TJs. My friends brother bought one. its terrible. yea its fast and it sounds great but we will probably spend the next 2 years redoing wiring. Stuff barely fits.

Meanwhile my crap box makes about 5psi boost with the supercharger. Stock motor, headers, etc. it still damn near lifts a wheel off the ground. People hate riding in it because its fast and clearly, unsafe. LOL

So is the V8 the problem or the poor workmanship?
 
If you want reliable, dont do an LS swap. Or any V8 swap. Its alot easier to work on the inline 6 than a v8. I finally saw one of these " cheap LS swap" TJs. My friends brother bought one. its terrible. yea its fast and it sounds great but we will probably spend the next 2 years redoing wiring. Stuff barely fits.

Meanwhile my crap box makes about 5psi boost with the supercharger. Stock motor, headers, etc. it still damn near lifts a wheel off the ground. People hate riding in it because its fast and clearly, unsafe. LOL

You haven't seen a GOOD V-8 swap then... You do know CJ's used to come from the factory with a V-8?

I'm on my third V-8 in a TJ and it's just as easy to work on the V-8 as it was the stock engine. And I'll take the added power everyday over a 2.5 or 4.0.

So is the V8 the problem or the poor workmanship?

Sounds like really poor workmanship....
 
My plan is to use holleys terminator kit with the dash to avoid issues like this.

Same but went AEM

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Update on the Jeep, the stock engine is still going strong at 10 psi even did an oil change on it and no metal at all in the oil, just a bit of a miss and lots of blowby, took it up north 4 hours away and got into some very deep mud (was up to the middle of the headlights) and screwed the clutch (release bearing is seized solid) and either the transfer case, trans or the rear diff is making a bit of noise only on decel so i suspect a loose bearing somewhere, also snapped an axle at home doing a WOT clutch dump LOL, so maybe that hurt something.

Going to hopefully be getting a house soon so will have space to tear it apart soon for the BEW TDI swap and repairs.

I'm a huge fan of LS engines myself, ive tuned many LS swaps and turbo setups for myself and others, they are about as simple as it get to work on, the Jeep 4.0 is awefull to work on in my opinion due to the intake and exhaust being stacked on top of eachother.

The main reason I want to go TDI is I dont want too much power as i know ill cam and boost an ls and start breaking jeep parts quickly.

This is the reason i love the LS engines so much, my Jaguar i built with a turbo 4.8 LS i sold it as i was sick of working on tranmission issues, had a built trans blow up on me after 3 tanks of fuel, was mid way into a borg warner super T10 manual swap and gave up on it, was on about 7-8 psi, ran a 13.2 in the 1/4 mile, i think im going to buy another less rusty one some day.

Will try to update again once i get the swap in motion, the adapter plate is the most expensive part at close to 2000CAD.
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Glad to see you’re still active. I bookmarked this thread a while back while doing research. Can you tell me if the HP tuner lets you change the aux fan on temp? I’d like to be able to kick it on at lower temps in my XJ when on the trails. Not sure if you can see that setting in a TJ.
 
Just wanted to start a thread for poeple to tag along with me and also share info on how to turbo a 4.0 as i found its very difficult to find needed and accurate info especially when it comes to tuning using HP Tuners.

To start off my Jeep is a 2002 TJ sport 4.0 5 speed manual 4" lift and 33s, 3.05 gears with factory LSD, and here is a list of parts going into the build.

Tuning software: HP Tuners
Tuner: Me (I have a backround in tuning for my self and customers, LS swaps, Hondas, DSM, SAAB, Ford, GM, and now Jeeps, using HP tuners, Holley, Megasquirt, etc. I do not have a shop its just a hobby for me)
Map sensor: GM 2 Bar part number: Delphi/GM 12247571 16040609
Wideband: AEM series X (i like the instant reading response these give)
Boost gauge: Glowshift (trying to keep this somewhat on a budget)
Turbo: Cheap $150 amazon with iternal wastgate (i have had very good luck with these lasting for years)
Boost controller: not using one, whatever the internal wastegate runs is what im running likely 5-8 PSI
Injectors: DW 39 LB kit for the Jeep 4.0 part number 18U-00-0039-6 (i love this company and use them in my builds and recomend them to everyone as they are great at posting proper injector data and i have yet to have an issue with any of them)
Intercooler: Not running one to start off as i like to experiment, will be adding one eventually and running it on top of the engine and adding a WRX style hood scoop.
Blow off valve: wont be running one as i like STUTUTU noises (this build is for fun)
Oil feed: generic universal diy kit
Oil drain: going to be testing out a no weld bulkhead style bung on this build out of curiosity, i usually weld in a bung on the pan, but the trucks at work use the bulkhaed style for fill tube and dipstick from the factory so wanted to give one a try and see if it leaks at all.
Air filter: i will be running a 3" inline filter as i want to run the intake from the turbo to the filter and then to a snorkel and have it water tight.

Incase you havent noticed im all about experimenting and having fun with things, its one thing to read something you read in a book or online and believe it, and another thing to do it yourself and learn from your observations and results.



The parts have been arriving for months and i finally got around to starting the build this weekend,

As of today I am at the point where the 2 bar map sensor and wideband are installed and the tune to run the jeep as it ran from the factory on a 2 Bar mpa sensor is complete, next will be to tune in the new injectors to run like factory, then and only after all this is done will the turbo install begin, this is by far the most straight foreward and accurate way to tune an engine if you are going for factory drivability, and one step at a time is also much better for if you run into issues which can be nightmares after changing out 20 plus parts and trying to figure out which one caused you slight hicup thats bothering you, or straight up no starts etc. One part at a time means one part caused the issue clear cut.

First step: GM 2 bar map sensor and tuning.
For tuning if will attach a basemap for a bone stock 2002 TJ 4.0 5 speed running on a GM 2 bar map sensor, I wrote this file myself, it is just a copy of the factory tune but scalled to work with the 2 Bar map sensor and not throw any codes, this actually to my surprise works flawlessly, the Jeep drives like factory, I logged before and after, timing is all perfect and fuel as well, long term and short term fuel trims are right on the money and closed loop, power enrichment, as well as cold and hot starts work as they did from factory.
If you care to see what all was changed feel free to compare my map to your stock file for a better understanding.

Everything in the fuel and spark tables above 52kpa is for boost as 52 kpa is now you new 105kpa in the maps, as you went from 1 BAR to 2 BAR, this is not as simple as cutting the table in half like some othr posts mention, you need to record idle KPA and key on engine off (this is the same as wide open throttle for an NA setup) KPA readings from the stock map then get the same readings from the new map then figure out what numbers in each table match up with eachother and carry over the numbers.

This gets confusing as not all map sensors have the same voltage curve so for example this 2 bar map reads 24-25 kpa at idle where the stock map reads 40kpa so numbers that used to be a 40KPA now belong in the 25 KPA bar, so its not as simple as cutting the tables in half, for WOT the stock sensor reads 103kpa and 2 bar reads 52kpa so WOT is more clear cut conversion, as for the numbers in between your best bet is to use the 3D visualizer in HP Tuners and makes the curves match what the factory curves look like, this is how i like to do it and it works well for me i copied the following bars from the stock map over to the new kpa bar for the 2 bar map 39-23, 65-31, 79-39 105-52, and of course dont touch the lowest bar as it stays the same, do this for all maps related to KPA and tweak a few other items to make the ECU happy and you have a perfect base map to work from.

keep in mind this is a stock map, to run stock injectors with a 2 Bar GM map sensor, aftermarket injectors will add complexity and will not be as striaght foreward as you then have to tune the characteristics in of the new injectors, whic almost never translates as easily as a new map sensor.

Link to the 2 BAR basemap file here as i cannot insert the file:
View: https://drive.google.com/file/d/151tGKwFkcYpebGB01wBlD_wZg3GV9peJ/view?usp=sharing

This is how i setup the MAP for now to test and tune, i will be doing a more permenant setup in the stock MAP location when i get time.

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And my jeep :)

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I know you posted this awhile ago i just finished putting a turbo on my 2001 jeep wrangler 4.0 and am alittle confused on What i need to tune the car in new to turboing and just want to get and idea on What i need to purchase and download
 
I know you posted this awhile ago i just finished putting a turbo on my 2001 jeep wrangler 4.0 and am alittle confused on What i need to tune the car in new to turboing and just want to get and idea on What i need to purchase and download

Like he said in the 1st post you need a HPT tuner to tune your PCM with. Then you have to buy credits to tune the PCM. The software is available on HPT's website for fee. Now as far as a known viable tune I can't help...
 
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